I have a 120 gallon tank with a over flow box in the center with four 1"bulkhead in the bottom.My plan is to use two of the 1"bulkheads for a herbie return drain and the other two for the supply back to the display. I'm going to use two syncra sdc 6.0 (530-1450 gph)plumbed separately. I'm not to concerned about head loss the sump is very close.Thoughts? Thanks